The godless move in mysterious ways: what the atheist bus campaign's advert will look like.

The atheist bus campaign launches today thanks to Comment is free readers. Because of your enthusiastic response to the idea of a reassuring God-free advert being used to counter religious advertising, the slogan "There's probably no God. Now stop worrying and enjoy your life" could now become an ad campaign on London buses – and leading secularists have jumped on board to help us raise the money.

The British Humanist Association will be administering all donations to the campaign, and Professor Richard Dawkins, bestselling author of The God Delusion, has generously agreed to match all contributions up to a maximum of £5,500, giving us a total of £11,000 if we raise the full amount. This will be enough to fund two sets of atheist adverts on 30 London buses for four weeks.

If the buses hit the road, this will be the UK's first ever atheist advertising campaign. It's an exciting development, which I never expected when I first proposed the idea on Cif in June. Back then, I was just keen to counter the religious ads running on public transport, which featured a URL to a website telling non-Christians they would spend "all eternity in torment in hell", burning in "a lake of fire". When I suggested the atheist counter-slogan (now shortened for readability), the response was extremely positive, and hundreds of you pledged your support after the follow-up article.

As you read this, a new advertising campaign for Alpha Courses is running on London buses. If you attend an Alpha Course, you will again be told that failing to believe in Jesus will condemn you to hell. There's no doubt that advertising can be effective, and religious advertising works particularly well on those who are vulnerable, frightening them into believing. Religious organisations' jobs are made easier because there's no publicly visible counter-view to refute their threats of eternal damnation.

The atheist bus campaign aims to change this. In addition to the slogan, the adverts will feature the URLs of secular, humanist and atheist websites, so that readers can find out more about atheism as a positive and liberating alternative to religion. We've also set up an interactive campaign website and Facebook group, so that questions raised by the adverts can be publicly debated.

CBS Outdoor, the bus advertising company, will run the atheist adverts in January if the funds are raised – but we need your help to make this happen.

Your donations will give atheism a more visible presence in the UK, generate debate, brighten people's day on the way to work, and hopefully encourage more people to come out as atheists. As Richard Dawkins says: "This campaign to put alternative slogans on London buses will make people think – and thinking is anathema to religion."